In computing, a hypervisor, also called virtual machine monitor (VMM), allows multiple partitions, such as guest operating systems, to run concurrently on a host computer. The hypervisor presents the guest operating systems with a virtual platform and monitors the execution of the guest operating systems. In that way, multiple operating systems, including multiple instances of the same operating system, can share hardware resources. Unlike multitasking, which also allows applications to share hardware resources, the virtual machine approach using a hypervisor isolates failures in one operating system from other operating systems sharing the hardware. With Advanced Memory Sharing, the hypervisor shares memory from a memory pool amongst the guest operating systems. In traditional approaches, the hypervisor receives limited information from the guest operating systems. This limited information can cause the hypervisor to incorrectly determine that a partition does not need as much memory, or needs more memory, because of the limited, and sometimes misleading, data metrics traditionally used with Advanced Memory Sharing.